Although she may want a Henry, and if so of course you get that for her, the ones I found with a quick web search looked like they have perhaps a gallon¹ capacity in the receiver tank, which isn't going to get you very far if you've got even an inch of water spread over a room sized area.

¹ 1 gallon = 231 cubic inches, => 1/2 inch deep ~20" x 20" per dump ?? => 23 dumps per 8' x 8' area ??

Your local lumber/home hardware outlet quite probably has "shop vacs" with 30 gallon (more or less) capacity that will do the flood cleanup more efficiently - and comparatively cheaply. A vac with at least a 5 gallon capacity would be the minimum size I'd consider "usefully efficient" for the area described. I use a 12-gallon regularly around the house, and have an 18 gallon in the "shop."

The shop-style wet/dry vacs may have slightly less "suck" but will have enough to get the water, and usually have little or no "filtering" to impede sucking up the silt/mud/hair/marbles and such likely to be brought in, or brought up, by flooding.

A high vacuum (lots of suck) is not what really counts for picking up water - it's the volume of air and the speed at which it moves that gets the water into the tank. Even if it's just seeped in throught the cracks, the water is likely to have lots of "contained material" better handled by an ugly piece, with the Henry reserved for final cleanup after the bulk of the water is removed.

(You'll likely have plenty of "finish cleanup" to do after you get the bulk of the water out.)

A good "shop fan" of perhaps 24" - 30" diameter that moves a lot of air even if it doesn't "blow really hard" will be a great help in getting the surfaces - esp. carpet - much dryer than any "sucker" can achieve. (You'll probably want to fan the area for some time after it looks/feels "dry" to avoid mildew in and under the surface.)

Just some thoughts for alternative and supplemental methods.

John